The Influence of Load and Ball on the Sliding Wear Characteristics of HVOF-Sprayed WC-12Co Composite Coating

This study examines the impact of various abrasive balls and sliding loads on WC-12Co coatings. For this purpose, 4 N, 8 N, and 12 N loads were applied to the WC-12Co composite coatings with Al2O3 and Si3N4 balls. WC-12 Co composite was deposited by the high-velocity oxygen fuel method on the AISI 304 substrate. The wear tests were conducted in accordance with ASTM G99 on a ball-on-disc tribometer at room temperature. In order to study the results of the coating tests, wear volume loss was measured against each counter body. Surface roughness and microstructure changes before and after wear were examined by electron microscopy. The resulting wear tracks were examined with an optical profilometer and the wear amount was calculated. When comparing the Al2O3 ball with the Si3N4 ball, the Al2O3 ball corrodes WC-12Co coatings more and is most susceptible to abrasive grooving, brittle cracking, and spalling. Wear rates rose by 77%, 58%, and 67% when the Si3N4 abrasive sample and the samples with Al2O3 coating were subjected to 4 N, 8 N, and 12 N loads, respectively. WC-12Co coating layers and powders were subjected to X-ray diffraction analyses, which revealed that coarse WC-12Co powder underwent less decarburization due to HVOF spraying.